Page 230 of 410

Getting out on the downhill (low) side ot a
vehicle stopped across an incline
is
dangerous. If the vehicle rolls over, you could
be crushed or killed. Always get out on the uphill (high)
side of the vehicle and stay well
clear of the rollover path.
Driving in Mud, Sand, Snow or Ice
When you drive in mud, snow or sand, your wheels
won’t get good traction. You can’t accelerate as quickly,
turning is more difficult, and you’ll need longer braking
distances.
It’s best to use a low gear when you’re in mud
- the
deeper the mud, the lower the gear. In really deep mud,
the idea
is to keep your vehicle moving so you don’t
get stuck. When you drive on sand, you”ll sense a change
in
wheel traction. But
it will depend upon how loosely
packed the sand is. On loosely packed sand (as
on beaches or sand dunes) your tires will tend to sink
into the sand. This has an effect
on steering,
accelerating and braking. Drive at a reduced speed and
avoid sharp turns or abrupt maneuvers.
Hard packed snow and ice offer the worst tire traction.
On these surfaces, it’s very east to lose control. On
wet ice, for example, the traction is
so poor that you will
have difficulty accelerating. And
if you do get moving,
poor steering and difficult braking can cause you to slide
out
of control.
Driving on frozen lakes, ponds or rivers can be
dangerous. Underwater springs, currents under the ice, or sudden thaws can weaken the
ice. Your vehicle could fall through the ice and
you and your passengers could drown. Drive
your vehicle on safe surfaces only.
4-25
Page 315 of 410

Buying New Tires
To find out what kind and size of tires you need, look at
the Certificationnire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue
to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service on
your vehicle. If your tires have an all-season tread
design, the TPC number will be followed by an
“MS” (for
mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires. Mixi-.,
--:es could cause
, - . o lose control
while driving. If you mix tires
of different sizes
or types (radial and bias-belted tires) the
vehicle may not handle properly, and you
could have a crash. Using tires
of different
sizes may also cause damage to your vehicle. Be sure to use the same size and type tires on
all wheels.
If you
--e bias-pi, ;ires c.. yo^. Jehicle, the
wheel rim flanges could develop cracks after many miles of driving.
A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
5-56
Page 316 of 410

Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width.
For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance. (This
applies only
to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
system does not apply
to deep tread, winter-type
snow tires, space-saver or temporary use spare tires,
tires with nominal rim diameters of
10 to 12 inches
(25 to
30 cm), or to some limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect
to these
grades, they must also conform
to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course. For example, a tire graded 150 would wear one and
a half
(1 5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart significantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction - AA, A, 9, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades represent the tire’s ability
to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned
to this tire is based on straight-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.
5-57
Page 319 of 410

lire Chains
Accessory Inflator
I^
Do.. - use tire ch-..ls. There’s no- _.__ugh
clearance. Tire chains used on a vehicle without
the proper amount of clearance can cause
damage to the brakes, suspension or other
vehicle parts. The area damaged by the tire
chains could cause you to lose control of your
vehicle and you or others may be injured
in a
crash. Use another type of traction device only if
its manufacturer recommends it for use on
your vehicle and tire size combination and road
conditions. Follow that manufacturer’s instructions.
To help avoid damage to your
vehicle, drive slowly, readjust or remove the device
if it’s contacting your vehicle, and don’t
spin your wheels.
If you do find traction devices
that will fit, install them on the rear tires. Your
vehicle may be equipped with an air inflator
system. You can inflate things like basketballs and
bicycle tires.
Also, you can use it to bring your tire
pressure up to the proper pressure. It is not designed to
inflate large objects which will require more than five
minutes to inflate, such as an air mattress.
To remove the cover, pull the two tabs on the cover and
pull
it off.
The air inflator kit may be located in the glove
compartment. The kit includes a
22 ft (6.7 m) hose with
three nozzle adapters.
5-60